Heat selection knob not working

Heat selection knob with my 95 Pontiac Grand Am is not working. The
heat always comes out from the front whatever selection I make. Is this
something easy to fix? If yes, how?

Thanks

the selection is controlled by a vaccum line which is somewhere by the firewall. i dont know how easy of a job this is, but i had the same thing happen to mine shortly after i bought it (it was still on warranty) so i took it to them and it took no more than a half hour for them to fix it. so it cant be too complicated to do yourself or it would be cheap to have a mechanic do.

what happens is the vaccum lines are notorious for going bad after a while, i dunno if they blow or if the seals leak or what. but it should be a fairly easy fix

sorry i cant offer more specific instructions.

The vacuum module is up in the dash behind the glove box. I have had the hoses come off before. Also follow the cable that comes from the selector knob. It has a plastic tab on it that controls a damper and I had it pop off once as well. I had no heat at all.